﻿using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApp3
{
    class yuan:Father 
    {
        public double a;
        public override void jisuan()
        {
            base.jisuan();
            Console.WriteLine("圆的面积为："+(3.14*a*a));
        }
    }
}
